tornadoError.py

#add this to your base handler class
def write_error(self, status_code, **kwargs):
    error_trace = None
    if self.settings.get("debug") and "exc_info" in kwargs:
      import traceback
      error_trace= ""
      for line in traceback.format_exception(*kwargs["exc_info"]):
        error_trace += line
    self.render("base_error.html", status_code=status_code, error_trace=error_trace)